1. Field of the Invention
The present invention relates generally to pressure test gauges. More specifically, the invention is a pressure test gauge for testing gas or air pressures during building construction.
2. Description of the Related Art
The related art of interest describes various pressure gauges, but none discloses the present invention. There is a need for pressure test gauges of different capacities to test building pressure systems. Moreover, the use of a color coded capacity indicia on a cover for these test gauges simplify the selection of a gauge having a suitable test range by the mechanic. The relevant art will be discussed in the order of perceived relevance to the present invention.
U.S. Pat. No. 2,518,540 issued on Aug. 15, 1950, to Donald C. Green describes a high pressure gauge comprising a scaled cylinder including a piston which moves against the force of a compression spring. The pressure gauge is distinguishable for its structure having a cup form closure on a distal end and a externally threaded extension for coupling to a fluid containing conduit to measure its pressure.
U.S. Pat. No. 4,136,560 issued on Jan. 30, 1979, to Alexander T. Gellos describes a tire mounted pressure gauge comprising a piston moving in response to pressure and giving a continuous readout. The piston has a position band that positions itself opposite the appropriate psi markings on the outside of the housing. The pressure gauge is distinguishable for its structure and its requirement to be permanently mounted on a tire valve stem.
U.S. Pat. No. 4,986,128 issued on Jan. 22, 1991, to Marvin D. Burns describes an in-line pressure gauge that uses a spring and piston to measure pressure in a gas line. A tubular adapter permits gas to flow into an annular chamber defined between an outer sleeve secured to the line adapter and a tubular plunger. The plunger, an annular seal, and a spring are retained on the adapter by the sleeve. The seal, plunger and spring are arranged concentrically about the adapter. Gas pressure forces the plunger out to indicate the pressure on the gauge. The pressure gauge is distinguishable for its plunger typical of present day tire pressure gauges.
U.S. Pat. No. 4,574,629 issued on Mar. 11, 1986, to Hsi-Kuang Weng describes a tire pressure gauge having an on-off means and being assembled from the tail end. The tire pressure gauge is distinguishable for its plunger type scale and being limited in use to measuring air pressure in tires.
U.S. Pat. No. 5,192,425 issued on Mar. 9, 1993, to Norman A. Cyphers et al. describes a mounting base and assembly for a pressure sensor, filter and pressure relief valve used in pressurized painting equipment. The assembly is distinguishable for its single-piece manifold and the limited use for painting equipment.
European Patent Application No. 0 634 185 A2 published on Jan. 18, 1995, for Ralph A. Milliken describes a digital dual pressure gauge. The gauge is distinguishable for its digital foundation.
PCT Patent Application No. WO 94/01746 published on Jan. 20, 1994, for Charles A. Liucci describes a high pressure gauge utilizing dual opposed springs, a pair of magnetic elements, and a flexible diaphragm. The pressure gauge is distinguishable for its different structure including magnetic elements for use in testing high pressures.
U.K. Patent Application No. 2,263,774 published on Aug. 4, 1993, for Tien-Tsai Huang describes a tire pressure indicator in the shape of a race car. The tire pressure gauge is distinguishable for its novelty shape and plunger mechanism.
U.K. Patent Application No. 2,267,170 published on Nov. 24, 1993, for Tien-Tsai Huang describes a tire pressure indicator including a signal producing transmitter for each tire transmitting a code unique to the tire and indicating whether the pressure is above or below the prescribed limits. The tire pressure indicator is distinguishable for its electronic mechanism.
None of the above inventions and patents, taken either singularly or in combination, is seen to describe the instant invention as claimed. Thus, a pressure test gauge assembly solving the aforementioned problems of having a set of interchangeable pressure gauges of different capacities on one valve body is desired.